Biofuels are now an important resource in the United States because of the Energy Independence and Security Act of 2007. Both increased corn growth for ethanol production and perennial dedicated energy crop growth for cellulosic feedstocks are potential sources to meet the rising demand for biofuels. However, these measures may cause adverse environmental consequences that are not yet fully und...

During decades, in semiarid rainfed Aragon, intensive soil tillage and low crop residue input have led to the loss of soil structure and soil degradation. Conservation tillage and cropping intensification can improve soil structure in these areas. The objective of this study was to determine the influence of three different tillage systems (traditional tillage, reduced tillage and no-tillage) u...

Tillage practices can influence crop root development. Root distributions were determined for wheat (Tdicum aestivum L.) grown in a wheat-fallow rotation during the 1977-1978 winter wheat crop year on an Alliance silt loam (Aridic Argiustoll). The fallow tillage treatments were plow, subtillage, and chemical (no tillage). Each tillage treatment was split into subplots for N application of 0 or ...

Microbial biomass nitrogen and carbon were studied in long-term field experiments with continuous cultivation of silage maize and with crop rotation. a positive effect of organic fertilizers on the microbial biomass nitrogen and the carbon content in soil was observed. Statistically significant effect of organic fertilizers on the higher content of microbial biomass C and n was established in t...

Bioenergy cropping systems have been proposed as a way to enhance United States energy security. However, research on soil physical properties, soil-surface CO2 effluxes, and soil drainage dynamics in such systems is needed to ensure environmental sustainability in the field. The objective of our research was to evaluate soil physical properties and conditions as well as soil-surface CO2 efflux...

Conservation tillage systems that reduce soil erosion and maintain or increase soil carbon offer long-term benefits for producers in the inland Pacific Northwestern United States but could result in reduced grain yields due to increased pressure from weeds, disease, and insect pests. Our objective was to compare runoff, soil erosion, and crop yields from a conventional tillage, wheat-fallow two...

Crop rotation is one of the oldest and most important approaches to the con­ trol of nematodes that feed on the roots of annual crop plants. The value of rotations often was recognized long before their effects upon the dynamics of nematode populations and communities were considered. As specific nema­ tode problems were identified and their economic importance demonstrated, attention usually w...

Nematicides are used to control a wide variety of nematodes on many crops; unfortunately, oftentimes the control they provide is erratic. This erratic behavior is not always predictable and has been associated with chemical, physical, and biological degradation of nematicides. Their accelerated degradation is an agricultural problem that has been observed in crop monocultures and in other crop ...

The use of soil and irrigation water with a high content of soluble salts is a major limiting factor for crop productivity in the semi-arid areas of the world. While important physiological insights about the mechanisms of salt tolerance in plants have been gained, the transfer of such knowledge into crop improvement has been limited. The identification and exploitation of soil microorganisms (...

CT crop–fallow system in the central Great Plains (Shanahan et al., 1988; Halvorson, 1990; Peterson et al., Winter wheat (Triticum aestivum L.)–fallow (WF) using conven1993; Halvorson and Reule, 1994; Farahani et al., 1998). tional stubble mulch tillage (CT) is the predominant production practice in the central Great Plains and has resulted in high erosion potential Winter wheat yields in a WCF...